The objective of this project is the research and development of analytical techniques which are used to: (1) establish the structure and purity of new antitumor agents and their metabolites, (2) determine physical and chemical properties of new anticancer drugs, (3) study reaction mechanisms and (4) quantitate drugs in physiological samples. Mass spectrometry, gas-liquid chromatography and high performance liquid chromatographic techniques are emphasized. Compounds of current interest are cytidine deaminase inhibitors, reduced nucleosides, seven-member nitrogen heterocycles, and aziridinylquinones. Silylation-mediated oxidation reactions are under investigation.